Error correction apparatus for reproducing data multi-encoded with error

Abstract

An error correction apparatus for reproducing data that have been multi-encoded with error correcting codes and recorded on a recording medium, and for correcting errors contained in the reproduced data through decoding the same. The apparatus includes: a reproducing circuit for reproducing the data encoded and recorded on the recording medium; a memory for storing the reproduced data; an error correction circuit adapted to correct errors of the data with the error correcting codes from the lowest to the highest levels in due order, for detecting that correction is impossible at the highest level and at an intermediate level between the lowest and the highest levels and for outputting a first and a second correction incapability detecting signals, respectively; and a controller responsive to the first and second correction incapability detecting signals for controlling the reproduction circuit, the memory and the error correction circuit. The controller controls the respective circuits to repeat error correction processing for the same data either until the errors are eliminated or until the retry number exceeds a certain limit number. Thereafter, the controller repeats the error correction processing up to the highest level either until the total retry number reaches a predetermined upper limit or until the errors are completely eliminated.